Pyoderma (Bacterial Skin Infections) in Dogs

Pyoderma (literally pus in the skin) varies depending primarily on the number of skin layers that are affected. Most cases of pyoderma are mild and treatable. Prompt veterinary care is required to stop the condition from worsening, and to address potential underlying causes.

Puppy pyoderma (also known as impetigo) occurs in prepubescent dogs.

Skin fold pyoderma occurs in breeds that have folds of skin where moisture and heat can get trapped. Some breeds of dog such as Sharpeis and Pugs have more folds than others and are therefore at greater risk.

Pyoderma also develops between the toes, typically when the dog gets damp during outings due to wet weather, walking in dewy grass, or swimming.

Deep pyoderma is most common in adolescent dogs, and is particularly persistent in some breeds including:

• Doberman pinschers
• German shorthaired pointers
• Great danes
• Bulldogs
• Boxers
• Mastiffs
• Weimaraners

Pyoderma is classified as superficial or deep, depending on how many layers of skin are involved. The deeper the infection, the more severe the case.

Severity also depends on the underlying cause of the condition. Dogs with allergies, endocrine disease, and other challenging conditions tend to develop pyoderma more regularly.

Some cases of pyoderma are persistent. They appear to resolve, but then reemerge. This may be due to premature discontinuation of antibiotics or underlying conditions like fungal skin infections.

The cause of pyoderma is a bacterial infection of the skin, most commonly Staphylococcus. These bacteria commonly live on the skin of dogs without causing symptoms. In certain circumstances they reproduce too quickly for the immune system to keep up and symptoms develop.

In some cases, the over-reproduction of the bacteria occurs because the layer of the skin that usually keeps the bacteria on the outside is damaged. This often happens due to skin trauma like a scrape or a bite wound, or when constant moisture has disrupted the integrity of the skin barrier.

Diseases of the endocrine system such as hypothyroidism or hyperadrenocorticism, or poor immune function can also decrease the skin’s ability to fight off infection.

Dogs with the symptoms of pyoderma require prompt veterinary attention. Diagnosis is based on physical examination and skin cultures.

Treatment of mild, superficial pyoderma is topical antimicrobial medications in the form of creams and shampoos.

Treatment of more severe, deep pyoderma or recurrent pyoderma sometimes requires antibiotics. Careful compliance with veterinary advice is required for use of antibiotics due to concerns over drug resistance in bacteria. Continuation of antibiotic therapy is required for the advised length of time, even when symptoms have resolved.

Attention to grooming is required for recovery from pyoderma. Long haired breeds benefit from professional grooming to remove trapped bacteria.

Treatment of underlying conditions is also necessary when applicable. Treatments vary depending on the specific underlying cause. For example, one of the goals of allergy treatment is to prevent secondary pyoderma, even though the allergies themselves cannot be cured.

Treatments for pyoderma take between one and 4 months to fully control the infection. In some cases, symptoms resolve quickly.

Prognosis for mild, superficial pyoderma is good to excellent. Severe, deep pyoderma, and pyoderma caused by underlying conditions have a more guarded prognosis.

For example, dogs with pyoderma as a result of skin folds trapping moisture and warmth are likely to require ongoing treatment unless the skin folds are surgically removed.

Dogs with atopy, food allergy, or flea allergy dermatitis are unlikely to improve without additional treatment for their allergic skin disease.

Strategies for the prevention of pyoderma include:

• Keeping the dog in good health
• Appropriate treatment of allergic skin diseases
• Avoid fleas and other parasites
• Avoiding skin trauma from bites and scratches
• Cleaning wounds
• Cleaning areas of skin where moisture gathers such as between the toes and inside skin folds
• Treating underlying causes early and effectively
• Routine bathing with medicated shampoos

Pyoderma is very common in dogs.